#include<bits/stdc++.h>
using namespace std;
 
int main(){ 
    double a,b;
    while(cin>>a>>b){
        if(b==0){
            cout<<"error\n";
            continue;
        }else{
            cout<<(int)((a/b)+0.5)<<endl;
        }
    }
    return 0;
}
